Islet allotransplatation has been demonstrated to greatly reduce or eliminate the requirement for exogenous insulin injection in patients with insulin-dependent diabetes mellitus. This experimental procedure offers diabetic patients hope for improved blood glucose regulation and, consequently, a reduced risk of long-term complications of the disease. In order to circumvent the problem of human donor tissue availability, the use of animal tissue, particularly that from the pig, has been studied in combination with a technology such as microencapsulation to "immunoisolate" the cells and prevent xenograft rejection. MicroIslets Inc. is developing an improved method for preparation of microencapsulated porcine islet cells for the treatment of Type I diabetes. MicroIslet has used technology licensed from Duke as a basis for generating improved methodology for the isolation, conditioning, storage and microencapsulation of islet cells. Here, we outline new methodology for porcine islet isolation whereby 400,000 islets will be harvested per pancreas. Preliminary data demonstrate that a singe intraperitoneal (ip) injection of encapsulated porcine islet cells prepared using this technology resulted in maintenance of normal blood glucose levels (100-150 mg/dl) in a previously diabetic baboon for 14 months, without the need for additional insulin injections or potentially harmful immunosuppressive drugs to prevent graft rejection. [unreadable] [unreadable]